Fatemeh Rouhi Dehkordi - Amirkabir University of Technology, Department of Aerospace Engineering, Iran

The purpose of this paper is to design and implement the Unmanned Aerial Vehicle (UAV) attitude control with nonlinear coupling dynamic equations, based on the sliding mode control (SMC) technique. The controller is designed by defining the appropriate sliding surfaces and Lyapunov functions and the desired attitude for the UAV is applied by the controller. The chattering phenomenon and oscillations of input signals was eliminated by modifying the Sign functions. The remarkable property of the designed controller is its high accuracy in spite of its simplicity. The validation is done by comparing with a chosen reference, and the validity of the controller performance is proved. The SMC works completely accurate with random initial conditions for all of the states and had robustness to the noise. Simulation results show that the performance of SMC is high and its accuracy is more than the feedback linearization method and the designed controller, make the UAV attitude exactly like the input commands, and for more accurate operations this controller is more appropriate.

Attitude Control, Unmanned Aerial Vehicle, Nonlinear dynamic, Sliding Mode Control, Chattering